A decade ago, Microsoft co-founder Paul Allen shut down Interval Research, a laboratory that employed more than 100 scientists, physicists and engineers to develop new technologies.

On Friday, Allen and his Seattle-based attorneys at Susman Godfrey unleashed a patent infringement lawsuit against some of Silicon Valley's heaviest hitters including Apple Inc., Google Inc., eBay Inc., Yahoo Inc. and Facebook Inc., claiming that they are infringing patents developed by the now-defunct company that he co-founded.

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Stanford Law School Professor Mark Lemley, who also is a partner at San Francisco-based Durie Tangri, questioned the patents.

"The patents appear to be quite old, and cover some very general concepts," Lemley wrote in an e-mail. "This raises the question: Why wait 10 years to license them?"